Coil winding machine

ABSTRACT

A coil winding machine for forming edge-wound or flat-on-flat coils, featuring an indexable and rotatable die, against which the material from which the coil is to be formed is held under pressure by a wiper bar. Edge-wound coils are acted upon by a wiper bar having a surface formed thereon which serves to motivate the coil turns upwardly as they are formed so as to make room for the incoming material. The flat-on-flat coils are acted upon by a powered roller wiper bar which is actuated so as to press the material against the die, and particularly about the ends thereof as the die is rotated.

United States Patent John A. McDonald Morton:

James B. Scotti, Pekin; Teddy R. Young, East Peoria; Roland K. Bass,Chillicothe, all

[72] Inventors of, III.

[21) App1.No. 811,750

[22] Filed Apr. 1, 1969 [45] Patented July 27, 1971 [73] AssigneeCaterpillar Tractor Co.

Peoria, 111.

[54] COIL WINDING MACHINE 12 Claims, 6 Drawing 1" 13$.

[52] U.S.C1 .1 72/142, 72/144, 242/82 [51] Int. Cl B211 3/04, 1302c19/00 50 Field of Search 72/142.

Primary Examiner-Charles W. Lanham Assistant Examiner-Robert M. RogersAtmrney- Fryer, Tjensvold, Feix, Phillips and Lempio ABSTRACT: A coilwinding machine for forming edge-wound or flat-on-flat coils, featuringan indexable and rotatable die, against which the material from whichthe coil is to be formed is held under pressure by a wiper bar.Edge-wound coils are acted upon by a wiper bar having a surface formedthereon which serves to motivate the coil turns upwardly as they areformed so as to make room for the incoming material. The flat-on-flatcoils are acted upon by a powered roller wiper bar which is actuated soas to press the material against the die, and particularly about theends thereof as the die is rotated.

PATENTED JULZ'! as?! SHEET 1 BF 4 INVENTORS JOHN A. McDONALD a m u m"JAMES B. SCOTTI TEDDY R. YOUNG ROLAND K. BASE}l )7 TT'ORNE COIL WINDINGMACHINE BACKGROUND AND SUMMARY OF THE INVENTION This invention relatesto a coil winding machine for forming coils from material such as fiatcopper. More particularly, the machine is designed to wind such coils ineither edge-wound (smaller dimension against the die) or flat-on-flat(larger dimension against the die) configurations. The coils are woundin automated operations during which hydraulically positioned wiper barsforce the copper material against the coil die at all times so as toproperly size the coil dimensions and eliminate all voids betweensuccessive coil turns.

One constantly sought after goal in the manufacture and use ofelectrical equipment is that of optimum physical size-tohorsepowerratio. To achieve this goal, special techniques have been devised toprovide proper insulation and electrical characteristics in componentssuch as main field and commutating field coils, while allowing suchcomponents to be ofthe smallest possible physical size.

One of the problems encountered in attempting to achieve this goal isthat of maintaining a tensioning pressure on square or rectangularcopper conductor material when forming elongated coils. In order to formsuch coils with precise internal dimensions, while preventing loosenessbetween adjacent turns in the end area where the copper must be formedin a small radius, a constant pressure must be maintained on theconductor material when both the coil end areas and the coil sides arebeing formed.

Some of the machines developed to produce these results have relied uponexternal counterweighted or friction tensioning devices which haveproven to result in relatively expensive processes. For example, windingmachines which employ external tensioning of'the copper require that theoperator stop the machine and pound each coil turn with a mallet toprevent looseness in the area of the coil ends. On the other hand, thecoil winding machines wherein the copper is wound upon a rotating diewith no tensioning means other than friction loading of the copper strapleading to the die require that the coil assembly be cold worked in apress for proper sizing and elimination ofinterturn voids.

It is therefore an object of this invention to provide a coil windingmachine which is capable of winding coils in edgewound or flat-on-flatconfigurations which obviates the disadvantages of known machines.

It is a further object hereof to provide such a machine in which coilsmay be produced having precise internal dimensions with no interturnvoids.

It is also an object hereof to provide a coil winding machine whichcombines a horizontal indexing table and a cross-slide to effect rotaryand transverse motion ofa coil die.

It is a further object hereof to provide such a machine wherein ahydraulically actuated backup ram slide with a wiper bar forms thecopper to the die compactly and tightly in all radius areas as well asin the straight areas.

It is a still further object of this invention to provide such a machinewherein the properly applied pressure of the wiper bar allows the coilto be formed without voids, while not requiring external counterweightedor friction tensioning devices.

It is also an object hereof to provide such a machine wherein edge-woundcoils can be made using a slotted wiper bar attached to the face ofabackup ram slide and disposed so as to always maintain pressure on thelower turn of the coil as it is being turned.

It is also an object hereof to provide such a machine wherein edge-woundor flat-on-flat coils may be formed merely by changing the wiper barsand properly positioning the material.

It is a further object hereof to provide the wiper bars which may beutilized in forming edge-wound and flat-on-flat coils.

It is a still further object hereof to provide such a machine which canform coils in a clockwise or counterclockwise configuration.

Other objects and advantages of the present invention will becomeapparent from the following description and claims as illustrated in theaccompanying drawings which, by way of illustration, show a preferredembodiment of the present invention and principles thereof and what isnow considered to be the best modes contemplated for applying theseprinciples. It is recognized that other embodiments of the inventionutilizing the same or equivalent principles may be used, and structuralchanges may be made as desired by those skilled in the art, withoutdeparting from the present invention an d purview of the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric illustration ofa machine which may be utilized to form the coils according to thepresent invention;

FIG. 2 is a plan view of the wiper bar which is mounted on the machineillustrated in FIG. 1;

FIG. 3 is a vertical section of the wiper bar of FIG. 2, taken along aline III-III therein;

FIGS. 4 and 5 show a front elevation and top plan view, respectively, ofa wiper bar which may be placed on the machine of FIG. I to form afIat-on-flat coil; and

FIG. 6 is anillustration of the operable portion of the wiper bar shownin FIGS. 4 and 5, as seen along a line VI-VI in FIG. 4.

DETAILED DESCRIPTION The Machine Referring to FIG. I, there is shown amachine which may be utilized to form coils according to the presentinvention, and which, as illustrated, is set up to form an edge-woundcoil from a rectangular copper workpiece.

Basically, the machine consists of a boxlike frame or table 10 in whichthe necessary electrical, hydraulic, and mechanical components tooperate an index table 12 and a cross-slide 14 are housed. A hydraulictank I6, hydraulic power unit 18, and electrical controls 20, all ofwhich permit control of the hydraulic fluid to be provided to thevarious components inside the frame 10, may be provided adjacent themachine.

In general, the control means may be ofa conventional electrohydraulictype wherein limit switches, solenoid valves, and hydraulic cylindersare arranged to produce the desired sequence of operation of the machineelements.

Although the below described series of events would occur for eithertype of coil configuration formation, the description will be set forthrelative to an edge-wound configuration so as to be in agreement withthe configuration illustrated in FIG. I. Further, the description willbe set forth for a clockwise winding of the coil, although it should berealized that simple reversal and adjustment of parts in an obviousmanner will allow the coil to be wound in a counterclockwise direction.

With reference again to FIG. 1, a flat copper workpiece 22, which may bedrawn from a reel or any other suitable fixture, is led through acleaning and straightening device (not shown) and placed flat on thehorizontal surface of the cross-slide 14 between a coil die 26, havingends 25 and 27 and mounted rigidly on the cross-slide and a wiper bar34.

Before starting the winding operation, the index table and cross-slidemust be properly positioned. This means that the table 12 must be sopositioned that a shot pin (not shown) actuated by a cylinder 46 engagesa slot 48 in the table to hold it against rotation. Further, thecross-slide 14 must be positioned at its extreme left position (asopposed to the illustrated extreme right position).

A pushbutton in a control panel 42 may then be activated to operate asolenoid valve which directs oil to a cylinder 30, exerting force on abackup ram slide 32 so as to move the wiper bar into position to receivethe edge of the copper material within a slot 35 in the bar. Thismaintains the workpiece flat against the slide 14 while holding ittightly against coil die 26. If desired, a set of ram pressure controls28 may be provided so that the pressure exerted on the workpiece may bevaried according to the requirements for forming different dimensionedcopper coils. The lead end 40 of the workpiece may be held by suitableretaining means (not shown) such as a pin and wedge block.

When this has been accomplished, a foot switch 44 may be actuated,causing the cross-slide 14, die 26, and workpiece 22 to move toward theright-hand side of the machine to the position shown in FIG. 1. This isaccomplished by means of a rack and gear unit generally shown at 50which is driven by a torque actuator 52.

When the cross-slide reaches the extreme right position, a limit switch(not shown) is actuated to operate controls which cause cylinder 46 towithdraw the shot pin from channel 48. Complete retraction of the shotpin serves to actuate another switch, causing a clutch actuatingcylinder 54 to operate. The clutch actuated by cylinder 54 causes a gear56 to be locked to its shaft 57 which, in turn, is fixed to theunderside of the index table 12. When the clutch is engaged by cylinder54, another switch is actuated causing a cylinder 60 to move a rack 58toward the front of the machine to rotate the gear 56. Since the gear 56is locked up to the table 12 via shaft 57, the table will rotate 180.

The controls then cause the clutch actuating cylinder 54 to disengagethe clutch, cylinder 46 to reengage the shot pin in channel 48, andcylinder 60 to move rack 58 to the original position-since gear 56 willnow rotate freely on the shaft 57. When the shot pin is in, the controlsagain cause the actuator 52 to function, driving the cross-slide 14 tothe right. The turning and indexing cycle is then repeated as often asnecessary.

If desired, a counter 62 may be provided to record one count for each360 movement of the index table.

During the winding operation, the wiper bar 34 maintains pressure on thelower turn of the coil, in a manner to be described, and provides wipingaction to form the copper tightly to the die as the table indexes andthe copper is bent around the die end. The shape of the finishededge-wound coil is that of a spring with elongated turns, when using thedie illustrated in FIG. 1. This edge-wound coil may be insulated afterwinding has been completed.

When winding flat-on-flat coils, i.e., the larger, flat part, of theworkpiece abuts the die. The same machine sequence is carried out, butthe copper must be fed to the machine in a position in which it isrotated 90 about its longitudinal axis from the position shown in FIG.ll. Thus, the narrow dimension of the workpiece is flat against theslide 14 and the widest dimension is flat against the side of the die26.

When winding flat-on-flat coils, the interturn insulation may be wrappedalong with the copper material as the coil is being formed. Theinsulation may be drawn from a spool of insulating material 70 which canbe mounted on either side of the table 111.

EDGE-WOUND COIL WIPER BAR Now with reference to FIGS. 2 and 3,illustrations are shown of two views of a wiper bar which may beutilized to form edge-wound coils.

The bar 34 has a top surface 111 which is ground so as to have a surface113 at an angle of from true right angle disposition to the upright ormounting portion 115 of the bar, A further slope 117 of 7, ground alongthe length of the bar, provides a 12 slope from horizontal for thesurface 117 when added to the 5 reference slope of surface 113.

The top surface of the bar then further ground at at 2 slope upward froma line 119, in both directions, resulting in equally sloped surfaces 121and 123 and an approximately one-sixteenth inch thickness of the topsurface at point 125. The radius of point 125 and the surface 127 ofslot 35 may be honed to a fine finish and chrome plated so as tominimize the abrasive action on the copper being formed. A rectangularplate 129 may be used to close the bottom of the conductor retainingslot 35.

In forming an edge-wound coil, when the die 26 reaches the extremerightward position, as illustrated in FIG. 1, the lefthand edge of thedie should be located opposite point 125 on the wiper bar. The table isthen rotated and indexed until the positions of ends 25 and 27 of thedie have been reversed. In other words, end 27 is now positionedopposite point 125. The end 411 of the workpiece then rides up on the 2slope on the top surfaces 121 and 123 and the next turn of the workpieceis held within slot 35. Die 26 may be slightly tapered so as to permitthe formed loops to move upwardly, and the turn to which pressure isapplied by the wiper bar is always at the bottom of the coil. Thus, aseach succeeding index of the die occurs, the next-to-the-last formedturn will ride up onto the top of the wiper bar.

Although the bar may be ground in a different fashion, it has been foundthat, with surfaces 121 and 123 at a 2 slope, the thicknesses of theedge of the wiper bar above slot 35-approximately three-eighths inch atthe left side of the bar, onesixteenth inch at point 125, andapproximately one-fourth inch at the right side of the bar-producesatisfactory formation of the coils.

Mounting holes 131 may be provided in upright portion 115 to hold thewiper bar to the backup ram 32.

FLAT-TO-FLAT COILS WIPER BAR As previously described, when it is desiredto form a flat-toflat coil, the workpiece 22 must be rotated about itsaxis. Further, the wiper bar 34 must be replaced with a bar 211 such asis illustrated in FIGS. 46.

The housing or body 213 of the bar 211 is formed with a channel 215extending its full length. The lower part of the housing is alsoprovided with a machined cutout 217, for reasons which will be explainedbelow. A pair of end closures 219 form flanged surfaces which aid inproperly positioning the wiper bar against the ram slide face plate.

A mounting block 221 is bolted to the left side of the housing 213 andcarries a plurality of stationary rollers 223 which ride on the uppersurface of the copper material. It also carries a plurality of rollers225 which bear against the flat, upright section of the workpiece.

A movable roller assembly, consisting of rollers 227, 229, and 231,attached to a lever unit 233, is fixed to a mounting block 235 by a bolt237, about which the lever unit 233 is pivoted, permitting rollers 229and 231 to be movable about the bolt.

As shown in the drawings, rollers 227 and 229 are mounted beneath thelever 233 and roller 231 is mounted on top of the lever. With the rollerassembly mounted to the wiper bar, roller 227 remains in line with therollers 225 regardless of the position of lever 233. On the other hand,roller 231 is free to move within the cutout 217 and roller 229 is freeto move about the end of the coil die 26.

A hydraulic cylinder 241, mounted on one of the end closure 219, has apiston rod 243 extending therefrom which is attached to the end of therectangular bar 245. The bar is slidably retained within the channel 215by inset cover plates 247,249, and the mounting block 235. A slot 251 ismachined in the lower edge of the bar and roller 231 fits within theslot.

When the assembly 211 is used in the coil winder, pressure is exerted onit by the backup ram slide to hold the copper material against the coildie. At the same time, cylinder 241 is pressurized to apply a force onroller 231 through bar 245. When the flat side of the coil die iscentered along the wiper bar, lever 233 will be turned in acounterclockwise direction, moving roller 231 to the left within cutout217, until the surfaces of rollers 225,227, and 229 are aligned andbearing against the copper material to hold it tightly to the coil die.

When the cross-slide has moved as far to the right as possible and thetable is indexed, the conductor material and coil die will move to aposition as shown in phantom FIG. 5 as the table is indexing, since thepressure in cylinder 241 forces roller 231 to the right within cutout217 when roller 229 is no longer against the flat portion of the die.Thus, rollers 227, and 229 maintain a force on the conductor material,causing it to be cold worked around the end of the coil die, eliminatingany possibility of looseness in the coil. When the table has beenindexed 180, roller 229 will have reached its limit in the clockwisepivot about bolt 237 and, when the cross-slide moves to the right again,lever 233 will be forced to move back in a counterclockwise directionagainst the pressure in cylinder 241.

As successive flat-on-flat turns are added to the coil, pressure ismaintained upon the assembly 211 by the backup ram slide 32 (FIG. 1) dueto the force applied by cylinder 30.

If desired, the hydraulic circuits for cylinder 30 and cylinder 241 mayinclude relief valves set to maintain the desired force on the backupram slide and the bar 245, causing the workpiece to be wiped around thecoil die and provide a coil of tightly wound construction with nointerturn voids.

As previously described, insulating material may be drawn from the spool70, shown in FIG. 1, and positioned between the turns of the coil as itis wound upon the die.

Thus, the Applicants have disclosed a coil winding machine whichproduces coils of much higher quality than those manufactured onpresently known machines. Further, wiper bars have been disclosed foruse with the machine of this invention which allow the production ofhigh quality coils of both edgewound and flat-to-flat configurations.Although only a single embodiment for each of these features have beenillustrated and described herein, it will be obvious to those skilled inthe art that many modifications and alterations may be made to theseembodiments within the scope of the following claims. For example, apositive linkage could be employed to replace roller 23!, bar 245, etc.,while attaining the same result in winding flat-to-flat coils.

lclaim:

l. A coil winding machine comprising a coil die, a flat surface uponwhich the coil die is mounted, a wiper bar positioned adjacent the coildie, means on the wiper bar for holding the workpiece against the coildie and against the flat surface, power means for exerting a force onthe wiper bar to hold a coil workpiece between the coil die and thewiper bar, and means to both rotate and translate the coil die wherebythe coil die moves both rotatively and transversely past the wiper bar.

2. The coil winding machine of claim 1 wherein the means on the wiperbar for holding the workpiece against the coil die and against the flatsurface comprises a slot extending along the workholding edge of thewiper bar to hold the workpiece against both the coil die and the flatsurface.

3. The machine of claim 2 including an upper surface on the wiper bar,and means on the upper surface forcing previously formed turns of thecoil away from the flat surface upon which the coil die is mounted.

4. The machine of claim 3 wherein the forcing means includes machinedportions of the upper surface.

5. The machine of claim 4 wherein the machined portions are sopositioned as to cooperate with the ends of the coil die as the coil dieis being rotated.

6. A coil winding machine comprising a coil die, a flat surface uponwhich the coil die is mounted, a wiper bar positioned adjacent the coildie, means exerting a force on the wiper bar to hold a coil workpiecebetween the coil die and the wiper bar, a first plurality of rollers onthe wiper bar holding the workpiece against the coil die, a secondplurality of rollers on the wiper bar holding the workpiece against theflat surface, and means to rotate and translate the coil die relative tothe wiper bar.

7. A coil winding machine comprising a coil die, a flat surface uponwhich the coil die is mounted, a wiper bar positioned adjacent the coildie, means on the wiper bar for holding the workpiece against the coildie and against the flat surface, means exerting a force on the wiperbar to hold a coil workpiece between the coil die and the wiper bar, alever mounted on the wiper bar, a plurality of work forming means Imounted on the lever, means in the wiper bar pivoting the lever aboutone of the plurality of work forming means, and means to rotate andtranslate the coil die relative to the wiper bar.

8. A coil winding machine comprising a coil die, a flat surface uponwhich the coil die is mounted, a wiper bar positioned adjacent the coildie, means on the wiper bar for holding the workpiece against the coildie and against the flat surface, means exerting a force on the wiperbar to hold a coil workpiece between the coil die and the wiper bar, alever mounted on the wiper bar, a plurality of work forming meansmounted on the lever, and means to maintain the plurality of workforming means in alignment with the means on the wiper bar which holdthe workpiece against the coil die when a flat surface of the coil dieis opposite the lever, but which moves at least one of the plurality ofwork forming means out of such alignment when a curved surface of thecoil die is opposite the lever.

9. A wiper bar comprising an elongated member having a slot extendingalong the length thereof and an upper surface thereon above the slot,the upper surface having at least one machined portion thereon at anangle relative to the main dimensional planes of the wiper bar, andwherein one machined portion of the upper surface is at an angle ofapproximately 5 relative to a plane extending from the slot, and asecond machined portion is at an angle of approximately 12 relative tothe plane extending from the slot.

10. The wiper bar of claim 9 including a third machined portionextending perpendicular to the one machined portion and the secondmachined portion.

11. The wiper bar of claim 10 wherein the third machined portion is atan angle of approximately 2 relative to the plane extending from theslot.

12. A wiper bar comprising means for holding a workpiece along at leasttwo dimensional surfaces thereof, and work piece forming means mountedon the wiper bar in alignment with the holding means which act upon oneof the dimensional surfaces of the workpiece, and means for moving atleast one of the workpiece forming means out of such alignment by apivotal movement of the at least one workpiece forming means about atleast one other workpiece forming means.

1. A coil winding machine comprising a coil die, a flat surface uponwhich the coil die is mounted, a wiper bar positioned adjacent the coildie, means on the wiper bar for holding the workpiece against the coildie and against the flat surface, power means for exerting a force onthe wiper bar to hold a coil workpiece between the coil die and thewiper bar, and means to both rotate and translate the coil die wherebythe coil die moves both rotatively and transversely past the wiper bar.2. The coil winding machine of claim 1 wherein the means on the wiperbar for holding the workpiece against the coil die and against the flatsurface comprises a slot extending along the workholding edge of thewiper bar to hold the workpiece against both the coil die And the flatsurface.
 3. The machine of claim 2 including an upper surface on thewiper bar, and means on the upper surface forcing previously formedturns of the coil away from the flat surface upon which the coil die ismounted.
 4. The machine of claim 3 wherein the forcing means includesmachined portions of the upper surface.
 5. The machine of claim 4wherein the machined portions are so positioned as to cooperate with theends of the coil die as the coil die is being rotated.
 6. A coil windingmachine comprising a coil die, a flat surface upon which the coil die ismounted, a wiper bar positioned adjacent the coil die, means exerting aforce on the wiper bar to hold a coil workpiece between the coil die andthe wiper bar, a first plurality of rollers on the wiper bar holding theworkpiece against the coil die, a second plurality of rollers on thewiper bar holding the workpiece against the flat surface, and means torotate and translate the coil die relative to the wiper bar.
 7. A coilwinding machine comprising a coil die, a flat surface upon which thecoil die is mounted, a wiper bar positioned adjacent the coil die, meanson the wiper bar for holding the workpiece against the coil die andagainst the flat surface, means exerting a force on the wiper bar tohold a coil workpiece between the coil die and the wiper bar, a levermounted on the wiper bar, a plurality of work forming means mounted onthe lever, means in the wiper bar pivoting the lever about one of theplurality of work forming means, and means to rotate and translate thecoil die relative to the wiper bar.
 8. A coil winding machine comprisinga coil die, a flat surface upon which the coil die is mounted, a wiperbar positioned adjacent the coil die, means on the wiper bar for holdingthe workpiece against the coil die and against the flat surface, meansexerting a force on the wiper bar to hold a coil workpiece between thecoil die and the wiper bar, a lever mounted on the wiper bar, aplurality of work forming means mounted on the lever, and means tomaintain the plurality of work forming means in alignment with the meanson the wiper bar which hold the workpiece against the coil die when aflat surface of the coil die is opposite the lever, but which moves atleast one of the plurality of work forming means out of such alignmentwhen a curved surface of the coil die is opposite the lever.
 9. A wiperbar comprising an elongated member having a slot extending along thelength thereof and an upper surface thereon above the slot, the uppersurface having at least one machined portion thereon at an anglerelative to the main dimensional planes of the wiper bar, and whereinone machined portion of the upper surface is at an angle ofapproximately 5* relative to a plane extending from the slot, and asecond machined portion is at an angle of approximately 12* relative tothe plane extending from the slot.
 10. The wiper bar of claim 9including a third machined portion extending perpendicular to the onemachined portion and the second machined portion.
 11. The wiper bar ofclaim 10 wherein the third machined portion is at an angle ofapproximately 2* relative to the plane extending from the slot.
 12. Awiper bar comprising means for holding a workpiece along at least twodimensional surfaces thereof, and workpiece forming means mounted on thewiper bar in alignment with the holding means which act upon one of thedimensional surfaces of the workpiece, and means for moving at least oneof the workpiece forming means out of such alignment by a pivotalmovement of the at least one workpiece forming means about at least oneother workpiece forming means.